The Tibetan Terrier diet will need to include animal proteins and carbohydrates, vitamins and minerals, and omega fatty acids--nutrients every dog needs to maintain its health in the long term. This means the best Tibetan Terrier food is premium dry kibble, as it has balanced portions of the above-listed ingredients.
Adult TTs, depending on their age, size, and activity level, will need about two cups of premium dry food per day, divided into two meals.. TT puppies will need a little less: again depending on age, about 1½ cups per day, divided into three meals (not two) until six months old.
For more info on feeding from puppyhood through maturity, here's a Tibetan Terrier feeding schedule:
Dog AgeDog WeightFood TypeAmountFrequency2 Months4 lbsDry (Puppy formula)0.25 cups3x/day3 Months7 lbsDry0.33 cups3x/day6 Months14 lbsDry0.5 cups3x/day9 Months18 lbsDry* (Puppy/Adult)0.85 cups2x/day12 Months+22 lbsDry (Adult formula)1 cup2x/day*--Around this time, transition to adult food by first mixing in a bit of adult formula with the puppy formula. Over the course of a week, with each meal add a little more adult formula to the mixture, until the dog is eating it entirely.
Try if possible to stick to the above-listed portions. Though they're not especially prone to obesity, if constantly overfed and under-exercised these dogs certainly can become overweight--and a fat Tibetan Terrier will have numerous health problems and a potentially shortened lifespan. You can help control your TT's weight by having consistent feeding and exercise schedules and by not leaving food in the dog's bowl all the time.
If you're worried your Tibetan Terrier is overweight, try this simple test: run a hand along the dog's side, and if you can't feel any ribs, it's diet time--which means less food and more exercise!